POPULATION-BASED STUDY OF THE INCIDENCE OF SUDDEN UNEXPLAINED DEATH IN EPILEPSY

Objective: To determine the population-based incidence of sudden unexp lained death in epilepsy (SUDEP) and to determine the risk of SUDEP co mpared with the general population Background: Prior studies of SUDEP have described a wide range of incidence and have suffered from select ion bias and other methodologic limitations. A population-based study of the incidence of SUDEP has never been performed. Furthermore, the r isk of sudden death in the epilepsy population has not been compared w ith that of the general population. Methods: All deaths in persons who se epilepsy was diagnosed between 1935 and 1994 in Rochester, MN, were reviewed. The rate of SUDEP was compared with the expected rate of su dden death in the general population for patients age 20 to 40 years t o determine the standardized mortality ratio (SMR). Results: We identi fied nine cases of SUDEP. SUDEP accounted for 8.6% (7 of 81) of the de aths in persons 15 to 44 years of age. The incidence of SUDEP was 0.35 per 1,000 person-years. SMR for SUDEP was 23.7 (95% confidence interv al, 7.7 to 55.0) compared with the general population. Conclusions: Th e incidence of SUDEP in our study was 0.35 per 1,000 person-years. SUD EP was responsible for 1.7% of deaths in our cohort. SUDEP is a rare c ause of death in the epilepsy population but exceeds the expected rate of sudden death in the general population by nearly 24 times.